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Bill Kielb

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  1. Like
    Bill Kielb got a reaction from Rae Reich in 100% ball clay projecting black dots after firing at 550 °C   
    550 c may get it done, just more time may be the secret and safest thing to try. I think even my self cleaning oven needs a few hours time to turn the simple organics to white ash at about 500c. I would try a 30 or 40 minute hold first, or even a slower ramp, say 100c per hour, then if no improvement gradually increase temperature. I see references to 630c as a common temperature to dewater.    I don’t think you will see  significant clumping issues until above 700c. So in the end, likely a balance between temperature and time you are willing to wait.
    As always, test to know for your clay, kiln, firing technique………etc
    If you do test, try and return here to post what works for you. It may help someone in the future.
  2. Like
    Bill Kielb reacted to Callie Beller Diesel in 100% ball clay projecting black dots after firing at 550 °C   
    @bijoy What are you making? There may be more than one way to get the results you want.
  3. Like
    Bill Kielb reacted to Hulk in 100% ball clay projecting black dots after firing at 550 °C   
    Please be careful supplying CO2 - such that your O2 supply is not displaced.
  4. Like
    Bill Kielb reacted to GEP in Help with error message   
    I’ll take a guess. P is for Power. F is for Failure. C is for … uh …. I don’t know. But anyways, was there a power failure at your house right before this code appeared?
  5. Like
    Bill Kielb reacted to Hulk in Help with error message   
    Am finding multiple references PF == Power Failure, however, none for PFC (kiln controller display).
    ...had fun looking though. Below is a representative excerpt.
    PF - Power Failure Power was lost during a firing and the kiln temperature was below 140 F (60 C) or the kiln temperature dropped more than 250 degrees during the power outage.
    Q. How do I clear the "PF" from the display?
    A. Press the "1" key. After several seconds the current temperature will be displayed. Several other numbers or STOP may be displayed before the current temperature.
  6. Like
    Bill Kielb reacted to Graham G in Help replacing Hobbytech 40 Energy Regulator   
    Thanks for your help guys. I started cleaning up the switch but decided it's too far gone inside and I'm better off replacing it. I spoke to Cromartie this morning and despite what the website says, they do have the part in stock.
  7. Like
    Bill Kielb reacted to ladyinblack1964 in Newbie needs advice/input   
    UPDATE:  I'm joining the handbuilding class midstream, starting tomorrow, and looking forward to it. From there, I'll see how ready I feel for any sort of open studio situation.
    Thanks to all of you for your help and input!
    Have a wonderful day!
  8. Like
    Bill Kielb got a reaction from Gusf in From 4 cuft to 12 cuft, finally got a big boy kiln!   
    Should be no insulation, it would be visible with a step in the sheet metal at the top.
  9. Like
    Bill Kielb got a reaction from 2Relaxed in Designing glaze blends for colors   
    Line blends for colorant work for most, progressing from light to dark so one test can generate many shades from one small sample. Hey don’t forget mason stains.
  10. Like
    Bill Kielb got a reaction from Pres in Designing glaze blends for colors   
    Line blends for colorant work for most, progressing from light to dark so one test can generate many shades from one small sample. Hey don’t forget mason stains.
  11. Like
    Bill Kielb reacted to Roberta12 in Same glaze different cone firing   
    I bought a few bottles of Stroke and Coat to use on earrings.  I tested on 2 clay bodies, and at 04 and 6.  I have been pleased with the results.  If I understand from reading the description, it is Stroke and Coat??
    Roberta
  12. Like
    Bill Kielb got a reaction from Hulk in Another KM1227 question   
    Just a couple observations FYI - Clay goes through quartz inversion up and down. For a glaze firing if your load has stopped let’s say within 300 degrees or more of its firing cone temperature then little heatwork was likely done so refiring  generally is not an issue. For bisque you can bisque fire pretty much as many times as needed within reason. Finally to make your cone drop at the temperature advertised on the cone chart, fire at the appropriate speed per the chart for the last 200 degrees. So for cone 6, center column (108 degrees per hour) fire to 2232   Starting at 2032. If you can fire per the chart, you stand a good chance at nailing your cone. Holds at top temperature can cause issues, do them only when you have a real confirmed reason to..
    Bisque firing only sinters  the clay together so not much melting. Bisque firing generally take longer to burn everything out so time at temperature is important. Many bisque firings range from 10-12 hours just to be sure to remove all organics.
    Quartz inversion just happens, up and down. Clay is tough, it generally can take it. Not much we can do about it.
    Typical glaze fire speeds 400-500 degrees per hour
    Typical Bisque speeds  approximately 200 degrees per hour
    Hope that gives you some ideas for future use.
  13. Like
    Bill Kielb reacted to Dick White in Same glaze different cone firing   
    The only way to know is to test it on you clay body. Some glaze recipes are quite robust and work over a wide range, and others are finicky within a narrow range. Even ones that are represented by the seller as having a wide range may respond differently on different clay bodies, both as to color and fit (shrinkage) over the range of temperatures.
  14. Like
    Bill Kielb reacted to neilestrick in Need Kiln Burner "Orifice Connector"   
    Try Ward Burner.
  15. Like
    Bill Kielb reacted to Callie Beller Diesel in Potter's Choice True Celedon 5 Gallon Clumping Issue   
    I would reach out to Amaco and ask them if they have any recommendations before making adjustments to your bucket. If the glaze already has some bentonite in it, adding more is going to not help, as a for instance.
    If you haven’t got the patience to wait for an email back, mix up your bucket again, and take some samples out to adjust as per the suggestions above (love Sue McLeod!). You don’t want to accidentally mess up your entire bucket.
     
  16. Like
    Bill Kielb got a reaction from Min in Potter's Choice True Celedon 5 Gallon Clumping Issue   
    Maybe someone with direct experience will answer but since this is a commercial glaze we have no idea of how much clay it might contain and if it is naturally deflocculated due to sodium. I suggest a good read for this  https://suemcleodceramics.com/how-to-fix-a-hard-panned-glaze-with-epsom-salts/
    You likely will end up using Epsom salt a little at a time to re suspend the glaze. Since bentonite can generally be added up to 2%, you might settle on 1% addition because you will never know the actual clay content, then flocculate with minimal Epsom salt as a start.
    Hopefully someone has direct experience with this commercial glaze for a tried and true solution. Actually a call into Amaco probably gets you the most tried and true solution for this glaze. I am sure they have seen it before.
  17. Like
    Bill Kielb reacted to Hulk in Potter's Choice True Celedon 5 Gallon Clumping Issue   
    Adding Epsom salt (or vinegar) to adjust thixotropy has been key turning glazing from chore to joy; here's Tony Hansen's video on the subject:
    How to Gel a Ceramic Glaze - YouTube
    Reducing "hard panning" is a side benefit for me; perhaps a nice "Gel" behaviour would be a side benefit for you Ken B? If you do increase the thixotropy, reducing specific gravity somewhat may be in order.
  18. Like
    Bill Kielb got a reaction from Hulk in Potter's Choice True Celedon 5 Gallon Clumping Issue   
    Maybe someone with direct experience will answer but since this is a commercial glaze we have no idea of how much clay it might contain and if it is naturally deflocculated due to sodium. I suggest a good read for this  https://suemcleodceramics.com/how-to-fix-a-hard-panned-glaze-with-epsom-salts/
    You likely will end up using Epsom salt a little at a time to re suspend the glaze. Since bentonite can generally be added up to 2%, you might settle on 1% addition because you will never know the actual clay content, then flocculate with minimal Epsom salt as a start.
    Hopefully someone has direct experience with this commercial glaze for a tried and true solution. Actually a call into Amaco probably gets you the most tried and true solution for this glaze. I am sure they have seen it before.
  19. Like
    Bill Kielb reacted to douglas in Gold Luster firing questions and schedule, help!   
    Remember that some of companies telling you the fumes are safe are the same companies that used encapsulated lead in frits into the 80s and 90s insisting that was food safe.  That doesn't prove they are doing the same thing with luster glazes, but I'd recommend erring on the side of safety and not being around the kiln when firing.
    Supposedly it is best to apply the luster as soon before firing as possible.  At least according to the potters I know who use luster.  I'd fire one piece, not all 8, so you can learn from the right amount of luster to apply. I've over and under done it, and the results are pretty ugly when not done right. 
  20. Like
    Bill Kielb got a reaction from Dayna in Gare Kiln   
    If you look at the label (equipment tag) posted above it appears Gare mentions directly what the maximum firing cone and temperature is for that particular  model.  3 rd line from the bottom. You may find your label tells you the kiln max firing temp, as well, read all the way through it is easy to miss embedded text.
  21. Like
    Bill Kielb reacted to Roberta12 in Underglaze pinholes and flaws - I don't understand why?   
    yes, more testing will happen.  It was such an easy project.  I used paper stencils on bone dry clay.  I have done that many times, but I usually thin my ug a bit.  And this surface issue didn't happen until glaze firing.  After bisque it was smooth.  I also discovered in that load that the 7 cone was down!  I haven't put cone packs in for awhile because I was out.  I will start doing that with more frequency.  
  22. Like
    Bill Kielb got a reaction from Gusf in pink glaze   
    Here is a mix percentage for various rutiles you may have use for in the future - no  significant chrome. https://glazy.org/materials/15393
    It takes roughly 2.12 parts more Magnesium carbonate to equal 1 part Magnesium Oxide. Magnesium Dioxide is not a typical glaze chemical so I assume you intended to use Magnesium Oxide.  So in your example above you would need approximately  3 g MgCO3 X 2.12 = 6.36 grams of Mag Carb (MgCO3) to equal 3 grams of Mag Oxide (MgO).. Magnesium carbonate does off gas or lose a great deal of its weight (Over half) when heated so it can cause other difficulties in some compositions.
    Here are some sample chrome tin recipes that may give you ideas when looking at their chrome and tin composition:
    https://glazy.org/recipes/77052
    https://glazy.org/recipes/32817
    https://glazy.org/recipes/79136
    The last recipe has some nice line blend info to show the variations in color vs different alumina levels for that recipe. Chrome tin recipes can be a bit of a challenge. See below line blend.
    Cobalt glaze: Mauve / Pink / Lilac here https://glazy.org/recipes/5542
    Careful with cobalt oxide and carbonate, same issue. You need just under. 1.5 times more Cobalt carbonate to equal 1 part oxide.

  23. Like
    Bill Kielb got a reaction from Roberta12 in Underglaze pinholes and flaws - I don't understand why?   
    If it helps we found color and thickness to be a primary cause. In our case we needed a tested glaze that worked pretty much no matter how the artist wanted to paint it else be accused of stifling creativity!  Hence the glaze solution. I think I only increased the boron a few points, so .15 to .19ish. Marcias matte is on glazy if you want to double check what it was brought up to. Anyway, IF this is your issue folks have been successful at adding a tiny amount of boron fritt or GB to their underglaze colors prone to this. Tiny amount seems to be key else the glaze chem locally is a mystery. Hope that helps.
    As usual tesssssst.
     
  24. Like
    Bill Kielb reacted to Min in Glaze Flaking off   
    @tzylawy, I'm copying the image you posted in the gallery into this thread so it's easier to find.
    Definitely wouldn't fire this as is. Was the glaze frozen at some point or is it really old? Also did you really stir it up before using? Did your brush drag as you were applying the glaze? Reason I'm asking is it looks like the gums that are typically used in brushing glazes are no longer effective. Is that the same glaze on the inside of the pot?
    I'ld scrape off as much glaze as you can (wear a mask), dump it back into the jar and scrub the outside of the pot. I'ld then add a little bit of gum solution and enough water to make a good brushing consistency and try it again on a test tile. If it works on the test tile then reglaze your pot. (it's easy to make your own gum solution if you don't want to buy it)
    Welcome to the forum 

     
  25. Like
    Bill Kielb reacted to JohnnyK in Kiln taking a long time to reach temp with new elements   
    I would check your wiring again just to be sure. If you didn't take pix when you took things apart, I would refer to the wiring diagram for your specific  kiln...
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